BehaveFun

BehaveFun is a behavior tree library for Ruby.

Inspired by gdx-ai's behavior trees.

Main features:

• Build behavior tree from Ruby and JSON.
• Serialize tree status data and can be restored later.

Installation

Add this line to your application's Gemfile:

gem 'behave_fun'

And then execute:

$ bundle install

Or install it yourself as:

$ gem install behave_fun

Usage

To build a behavior tree:

builder = BehaveFun.build_builder {
  # add_task_type YourCustomTask
}
# ruby dsl
tree = builder.build_tree { success }
# from hash
tree = builder.build_tree_from_hash(type: :success)
# from json
tree = builder.build_tree_from_json(json_string)

To build a complex behavior tree:

# write_spec, write_code, run_spec, git_push and release_gem are customized tasks
tree = builder.build_tree {
  sequence {
    until_success {
      sequence {
        write_spec
        write_code
        run_spec
      }
    }
    git_push
    release_gem
  }
}

To create customized task, create a class that extends BehaveFun::Task (or use a lambda if only need to overwrite #execute method). Don't forget call running success or fail in #execute method at the end.

# a task that increase data by 1, always success
class Counter < BehaveFun::Task
  def execute
    context[:counter] += 1
    success
  end
end

# a task that detect tree data is even or not
is_counter_even = -> { context[:counter].even? ? success : fail }

# add these tasks to your builder
builder = BehaveFun.build_builder {
  add_task_type Counter
  add_lambda_task_type :is_counter_even, &is_counter_even
}
builder.build_tree { counter }

To run a tree:

tree.context = { ... } # provide your context (data) for the tree
tree.run
tree.status # :running, :succeeded or :failed

To dump and restore status:

status = tree.dump_status # a hash that contains entire tree's status
tree.restore_status(status)

For more detail, see spec examples.

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/ayamomiji/behave_fun. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the code of conduct.

License

The gem is available as open source under the terms of the MIT License.

Code of Conduct

Everyone interacting in the BehaveFun project's codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.